The closest analogue of the claimed technical solution is the device by the patent serial number U.S. Pat. No. 9,783,261 B2, Oct. 10, 2017, “Dismountable device for transformation of treadle lever rocking movement into rotary movement of bicycle drive shaft», publication date: Jun. 2, 2016, by the inventor, Efim Gimpel. This device is implemented in the form of two identical sprockets on the axis of simultaneous swing of each pedal lever around the axis of rotation of the bicycle drive shaft, connected in pairs by two bicycle chains with tension springs connecting both ends of the chain, with sprockets mounted singly at each outer end of the shafts reversed by the reducer, whose rotation axes are parallel to the axis of swing of the pedals, with the upper and lower sprockets rotating in pairs in one of the planes perpendicular to the axis of rotation of the bicycle drive shaft.
The main disadvantage of the above analogue is the usage of flexible links in the form of bicycle chains for the transmission of the working force to bring into oscillatory motion the pedal levers, said levers sitting on the working axis of rotation of the bicycle drive shaft through a single-stage reducer. However, during the working operation of the bicycle under the influence of tensile forces of the chain due to the natural gaps and wear of individual elements of the chain, the chain can jump off the driven sprockets, which requires the use of tightening devices while using the bike, and which complicates the conditions of its operation and reduces the reliability of the design.